C'était on ne peut plus plaisant.
I could not understand this sentence using the wordreference dictionary; I had to enter it into Google Translate, and I still don't understand how to arrive at the meaning GT gave me: "It could not have been more pleasant".
1) I don't understand how the subject pronoun "on" can directly come after "C'était".
More typical examples of "C'était" being used, is an adjective ("rouge") or adverb ("lentement") or perhaps noun folows. But it seems like a mini-sentence is following "C'était" in this case, which I never encountered before.
2) If I try to translate the "on ne peut plus plaisant" part, I get "we no longer can .. ?? pleasure". I see an adjective following "peut", which is as strange as me saying "Il peut rouge". I expected a verb to follow peut ("Il peut dancer"), but not an adjective.
1. What does this sentence mean?
2. How is it that "on" follows "C'était"?
3. How is it that an adjective follows "peut"? And why is "peut" conjugated in the present tense, when the entire story is conjugated in one of the three past tenses?
4. How does a sentence that means something like "It was - we no longer can - pleasure" actually mean "It couldn't have been more pleasurable"?